package zy0157;

public class Demo {
	public static void main(String[] args) {
		Thread1 t1=new Thread1();
		Thread2 t2=new Thread2();
		Thread3 t3=new Thread3();
		Thread4 t4=new Thread4();
		t1.start();
		t2.start();
		t3.start();
		t4.start();
	}
}
